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<div align="center"> <font size="5"> <b><font face="Arial, Helvetica, sans-serif"><a name="top"></a>MCCCS
Towhee (Square Well)</font></b> </font> </div>
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<td width="697" valign="top"> <b>Overview</b>
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This section covers Square Well parameters as they are implemented into the towhee_ff_SquareWell file in the ForceFields
directory. It is a bit strong
to call this a force field, as all there is not much to a square well
potential, but this file explains
how to use the builder with the square well potential, and how to add
in any other square well parameters that
you might want to use in a simulation.
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<b>Square Well in Towhee</b>
<ul>
The official force field name for Square Well in Towhee is 'SquareWell'. Here I list all of
the Square Well atom names currently in use for the towhee_input file,
along with a brief description (although the meaning of the atom names should be obvious).
If you want to add any new parameters into Towhee just take a look in the
<a href="../potentype/towhee_input_classical_potential.html">towhee_input
classical_potential</a> documentation
for a complete description of the functional form. I am happy to add
some more of these parameter sets into the release version as well
(only takes a few minutes). The distance units are in Angstroms, and
the well depth is in Kelvin divided by Boltzmann's constant.
Please note that the capitalization and spacing pattern is important
and must be followed exactly as listed here.
<ul>
<li><b>'type_a'</b> : sigma [nbcoeff(1)] is 1.0, lamda [nbcoeff(2)]
is 1.5, and the well depth [nbcoeff(3)] is 1.0.</li>
<li><b>'type_b'</b> : sigma [nbcoeff(1)] is 2.0, lamda [nbcoeff(2)]
is 3.0, and the well depth [nbcoeff(3)] is 1.0.</li>
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<b>Coulombic interactions</b>
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It is possible to combine the square well potential with point charges. Simply assign the point charges to the
atoms as you see fit.
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<a href="../towhee_capabilities.html">Return to the Towhee Capabilities web page</a>
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<i><font size="2">Send comments to:</font></i> <font size="2">
<a href="mailto:marcus_martin@users.sourceforge.net">Marcus G. Martin</a><br>
<i>Last updated:</i>
<!-- #BeginDate format:Am1 -->September 07, 2005<!-- #EndDate -->
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